The difference, however, is the understanding and resources necessary to deal with the problem remain scarce here, said Dr Nittaya J Kotchabhakdi, a paediatrician involved in studies of sleep disorders in children at Ramathibodi Hospital.

Recent research found that about 38 per cent of Thai adults suffered a moderate degree of sleep problems and 15 per cent had severe problems, said Assoc Prof Naiphinich Kotchabhakdi, director of Mahidol University's Neuro-Behavioural Biology Centre.

The figures were very close to the global statistics compiled by the World Health Organisation, he said.

"Sleep disruption contributes to about 20 per cent of road accidents in Thailand," said Naiphinich.

Caused by various factors including lack of sleep and alcohol consumption, sleeping at the wheel was the main cause of road accidents in the country, he said.

Recent studies in the West had also linked sleep problems to many other ailments including strokes, coronary heart disease, type 2 diabetes and high blood pressure, said Naiphinich, who is a leading researcher in the new field of "sleep medicine".

People with poor sleep hygiene were also found to have emotional and behavioural problems, he said.

Nittaya said her research had found that about one-fourth of children suffered sleep problems between birth and 18 years of age.

As in adults, the most common problems included insomnia, disrupted sleep, nightmares, lack of sleep and sleep apnoea, Nittaya said.

The problem of lack of sleep, for example, was found to get worse as children grew older, she said, adding that getting to sleep late and waking up late was of particular concern in teenagers.

Nittaya's study, which was conducted on 1,600 people, including 315 teenagers, in five provinces - both rural and urban, found that as many as 35 per cent of the teenage sample group had sleep problems.

She said people with problems, such as lack of sleep, were found to have emotional and behavioural disorders, but added: "We cannot say exactly that sleeping problems were the direct cause of these problems, but they are associated."

Teenagers with sleeping problems were also found to lose the ability to work or study normally six days per week, compared with only a day per week in normal counterparts, Nittaya said.

And ongoing study at her department has even found an alarming trend of sleeping problems in infants, she said.

"So all ages of people are affected by sleep disorders to some extent," she said.

Apart from outside factors such as bad sleep habits, sleeping disorders could also be caused by physical and mental factors, said Pichet Udomrat, a professor of psychiatry at Songkhla University's Sleep Disorders Service and Research Centre. These factors include certain diseases including Parkinson's, strokes, depression and anxiety disorders, said Pichet, who is also the president of the Psychiatric Association of Thailand.

To raise awareness about the importance of sleep hygiene, Thailand will host the 2nd World Congress of Sleep Medicine in Bangkok in February in conjunction with Association of Sleep Medicine. The first congress was held in Berlin a couple of years ago.

Arthit Khwankhom

The Nation